Cytisine therapy for tobacco smoking cessation: a retrospective observational study from an Italian anti-smoking center

OBJECTIVE: Tobacco smoking is recognized as one of the biggest threats to public health globally. Clinical trials conducted to date on cytisine have demonstrated its good efficacy in promoting smoking cessation. This study aims to evaluate the effectiveness and tolerability of cytisine as monotherapy in the treatment of moderate or severe tobacco use disorder in a real-world setting in Italy.MATERIALS AND METHODS: A monocentric, retrospective, observational study was conducted on 159 adult patients (≥18 years) treated with oral cytisine who were referred to the Rome Anti-Smoking Center of IRCCS Regina Elena National Cancer Institute for the first time from March 2023 to November 2023. The study used both clinical [objective examination, Visual Analogue Scale (VAS) test, Fagerström test, and Mondor test] and instrumental evaluations (spirometry and measurement of exhaled carbon monoxide). Categorical data were summarized using absolute frequencies and percentage values, while continuous variables were summarized using median values and relative range. Comparisons between categorical variables were performed by using Pearson’s Chi-square test or Fisher’s exact F-test. Comparisons between continuous variables were carried out using the Mann-Whitney test or the Student’s t-test. The non-parametric Wilcoxon test was used to compare carbon monoxide values between the first visit and the first follow-up visit.RESULTS: 93 (58.5%) patients were males with a median age of 64 years, while 66 (42%) were females with a median age of 63 years. The median age of cigarette smoking initiation was 16 years, and the median number of packs per year was 40. After 3 months, 44 patients out of 65 (67.7%) patients who received therapy were adherent, while 21 (32.3%) patients did not follow the prescription and dropped out of the treatment. 75% (33/44) of patients who adhered to therapy successfully quit smoking, compared to just 25% (11/44) of those who did not adhere to treatment and did not stop smoking (p=0.011). No significant safety issues were identified.CONCLUSIONS: Cytisine therapy administered in the real-life setting of a specialized anti-smoking center significantly promotes smoking abstinence. However, it has a poor therapeutic adherence profile, requiring further research on therapeutic adherence and long-term outcomes in order to optimize treatment strategies.